JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
  <form role="form">
    <div class="form-group">
      <select id="select" class="form-control" >
<option value="1">a</option>
<option value="2">d</option>
<option value="3">b</option>
<option value="4">c</option>
</select>
    </div>
  </form>
</div>

JavaScript

var items = $('#select option').get();
items.sort(function(a,b){
  var keyA = $(a).text();
  var keyB = $(b).text();

  if (keyA < keyB) return -1;
  if (keyA > keyB) return 1;
  return 0;
});
var select = $('#select');
$.each(items, function(i, option){
select.append(option);
});